AIS is a condition that affects the development of the genitals and reproductive organs from birth. The development of female or male genitals is governed by which pair of sex chromosomes the baby receives -- XX for a female or XY for a male
- A child with AIS is born with a set of genetically male sex chromosomes. The presence of the Y chromosome stops the development of internal female reproductive organs and causes the development of testes as in normal male sexual development. In AIS cases, the hormone androgen, which the testes release and is responsible for the development of a penis, is suppressed. As a result, the genitals develop along female lines and the testes usually remain inside the body
- There are two forms of AIS. Complete androgen insensitivity syndrome (CAIS) is where the person develops entirely female genitals. In these cases, the child is usually raised as a girl. Partial androgen insensitivity syndrome (PAIS) is where the person can look almost entirely male, entirely female, or somewhere in between. Children with PAIS can be bought up as girls or boys. The decision is often based on the degree and type of genital development
- AIS is caused by a mutation in the gene that produces androgen receptors. Sufferers will require hormone therapy and psychological support and some also have reconstructive surgery at a young age to establish the gender that has been decided for them
9% of women with CAIS develop cancer
1 in 20,400 male births affected by AIS
1 in 3 cases of the AIS mutation occur at conception
Source: NHS Choices
